Candida

Many species of yeast within the genus “Candida” make their home in the human body. Anywhere a moist, warm environment with a favorable pH factor exists, yeast such as Candida are likely to be present, usually in a harmless coexistence with other microflora. However, when stress, an oversupply of sugar, or prolonged exposure to heat occur, the Candida yeast tends to overpopulate and create a spectrum of illnesses which are uniquely irritating to the body part they inhabit. Helpful bacteria such as Lactobacillus appear to play a major role in maintaining the body’s control of Candida at optimum levels. However, when Candida is uncontrolled by helpful bacteria, many infections and complications can occur.

In infants, a yeast imbalance within the mouth is known as “Thrush.” The obstetrics field is attempting to reduce these occurrences by identifying prenatal factors that contribute to this type of yeast overpopulation. It is believed that infants are exposed to the mother’s indigenous yeast populations in the birth canal, so prenatal treatment of the mother may be an effective manner of recapturing the natural balance of helpful bacteria versus yeast.

Obstetricians in Poland and Belgium attempted to identify whether the presence of Candida in the birth canal was related to age, antibiotic use, or cigarette smoking. The aim of this 2007 study was to evaluate the correlation between Candida isolated from pregnant women and the environmental factors such as mother’s age, cigarette smoking and antibiotic treatment that may have an influence on the microfloral balance of the vagina. Fifty pregnant women were examined, ages 18-40 years old, after admission to three different obstetric departments in Poland. The vaginal samples were tested for aerobic bacteria, Gardnerella vaginalis, Lactobacillus and Candida. Candida was found in 21 samples or 43%. A correlation was found relating to age and the presence of Candida. Younger pregnant women were more likely to be colonized by Candida. No influence on bacterial composition was correlated to tobacco smoking or antibiotic treatment. This study questions the assumption that antibiotic use is connected to an imbalance of Candida, and raises many more reasons to study Candida and Lactobacillus patterns as they may affect infants and mothers during prenatal care.

Yeast imbalances occasionally occur on the skin, near folded areas that promote a moist environment. They can create an irritated, red appearance, but are often treated with over-the-counter ointments such as Lamisil and Tinactin, which contain fungicidal agents. In children, we often call this red prickly skin eruption a heat rash. In men, this is often referred to as jock itch, and many topical sprays are available to reduce the irritation.

A more dangerous form of yeast or Candida imbalance is known as the systemic yeast infection, where the entire immune system is compromised by yeast entering into the bloodstream, also called Candidemia. The occurence of these systemic infections was on the rise in Swedish hospitals when a nationwide study was launched to explore the causes of fundicide-resistant Candida in 2006. If consumers were overusing fluconazole for over-the-counter self-treatment, they hypothesized, then highly resistant forms of Candida might be on the rise.

Earlier surveys of yeasts causing bloodstream infections in Sweden revealed a relatively high occurence of Candida species that were resistant to azole antifungals. Since pharmacies in Sweden are government-operated, statistics on the consumption of antifungals can be obtained from The National Corporation of Swedish Pharmacies. This information showed a 10-fold increase in the use of the triazole fluconazole from 1990 through 2005. The government of Sweden took precautions to catalogue and identify every strain involved in cases of Candidemia, in almost 100% of the cases occuring in 2006. In regions where fluconazole use was high, the resistant Candida strains appeared to occur more often, raising future concerns as to how to control and prevent blood infections of this type. Candidemia occured in 2006 at the rate of 4.3 episodes per 100,000 population, according tho this study, and many of the blood cultures analyzed by the Swedish government’s mycology unit found fundicide-resistant Candida strains as the cause of this illness. The study calls into question whether the widespread use of fluconazole as an over-the-counter symptom reliever may be shortsighted and damaging to microfloral balance in the long run.

The occurence of yeast-based vaginitis is far more widespread than blood infections. In fact, in women from the ages of 18 through 78, they are a commonplace irritant. Throughout a woman’s lifetime, she has a 70% chance of experiencing at least one vaginal yeast infection, or Candidiasis. This illness affects an overwhelming majority of females at some point in their life, and is caused by an imbalance of the microflora in the genital tract.

In a recent 2008 study conducted at the Kinki University of Japan, the microbial flora of the lower genital tract in adult females were examined. The study observed that the female genital tract has a very complex microbial flora, constantly changing under the influence of monthly hormone cycles and sugar levels. The Japanese study revealed that the presence of a type of sugar known as glycogen within the vaginal mucosa was partly controlled by the secretion of estrogen and progesteron, with helpful bacteria as a contributing factor. In addition, a large population of Lactobacilli helps to maintain the pH of the vagina and external cervical ostium. The optimum pH appears to occur between 4.4 and 4.6, but E coli is inhibited from growth at a pH of less than 5. Because Lactobacilli are known to be helpful in generating an appropriate acidic level to inhibit harmful bacteria, the presence of certain bacteria in the vagina appears to be critical in maintaining a healthy pH level. Lactobacilli may also play a role in helping the genital area to adapt to changes in sugar levels. A total of 238 women were examined in this study, and the most frequently detected microflora were Lactobacilli, Corynebacterium, and Staphylococcus epidermidis.

The Japanese study found that vaginal microbial flora was influenced by inflammation, malignant lesions, and by the age of the subject. Age was the most important factor in predicting which microflora would be present. Lactobacillus and Candida albicans were detected more frequently in younger women. However, Pseudomonas aeruginosa and Bacillus were frequent among the older women who participated in the study (subjects greater than 50 years old). The Japanese study concluded that microflora adjusts to its environment when the ovaries are active, and likewise readjust when the ovaries become less active after the childbearing years are over. To draw an inference from these study results, a future challenge for the probiotic industry may be to offer products that are specifically aimed at particular age groups of women, who may experience vaginitis from different species of microflora in each decade of their lifelong reproductive stages.

The Australian medical team of Marie Pirotta and Suzanne Garland has produced studies of Candidiasis which are wide-ranging in terms of large sample populations. In order to confirm scientifically whether antibiotics do indeed have a negative affect on the microflora of the female genital tract, they sampled over 200 women just before taking antibiotics, then again after the course of antibiotics was complete. This Australian study was conducted in 2006. Study participants were required to have no vaginal symptoms prior to entering the population sample, and be taking antibiotics for a non-genital condition.

In the Australian study, the proneness to Candida-related vaginitis was significantly raised after the 200+ women in the sample took a prescribed dose of antibiotics. Candida was present in 21% of the women before they took antibiotics, and increased to 37% afterwards. The species of microflora found after antibiotic treatment varied significantly among the subjects: Candida albicans was the most prevalent before and after treatment, rising to over 70% of vaginitis-infected subjects in the after-antibiotic samples, but Candida glabrata was also detected in around 20% of the post-antibiotic cases of vaginitis. The study concluded by encouraging physicians to test for definitive microbial evidence before assuming Candida albicans is the cause of vaginitis, especially for patients with a tendency towards recurrent symptoms. The study recommended that when physicians prescribe antibiotics, the history of vaginitis should be discussed so that the least aggressive therapy can be recommended for those patients. The Australian team in this study stopped short of recommending probiotics, but their contribution is significant with regard to causes and effects related to Candida colonization.

From a review of these studies and several others, it appears that the widespread reliance on fluconazole has generated some risks of inaccurate self-diagnosis. Consumers may assume they have one form of Candida, when sometimes another species is the cause. Sometimes the symptoms of a yeast infection mask other medical problems like Chlamydia, which is not cured by anti-fungal agents. Unless a species-specific microbial diagnosis is conducted by medical personnel, it is possible that another condition can go undiagnosed and untreated. The widespread use of antibiotics also appears to harm the balance of helpful bacteria, especially with regard to female genito-urinary health. When broad-spectrum antibiotics are prescribed to patients with recurrent cases of yeast-based vaginitis, a cycle of detrimental yeast imbalance is likely to be the result. Better diagnostic tools and improved therapies are needed for the challenge of Candida overpopulation.

A preferred method of restoring the yeast microfloral balance may be offered by probiotics, especially as a preventative or prophylactic approach. Just as yogurt is often recommended during and after taking antibiotics, in order to help restore the bacteria that controls yeast infections, probiotic supplements may also be helpful. Sugar levels and pH balance also contribute to the conditions that encourage overpopulation of Candida. Lactobacillus appears to benefit pH levels in the digestive tract and in the genital tract, to the detriment of Candida, but the exact mechanism by which this occurs in the genital tract is not yet understood fully. Additional study of probiotics in humans is likely to reveal new therapies for yeast-based vaginitis and other illnesses caused mainly by the imbalance of Candida. Unlike fungicides and antibiotics, probiotics display the advantages of having no major side effects, and not contributing to the development of super-resistant Candida strains. Due to the relative mildness of probiotics compared to these other therapies, their use as a balancing mechanism shows a great deal of potential.

“Genital Candida Species Detected in Samples from Women in Melbourne, Australia, before and after Treatment with Antibiotics.” Marie V. Pirotta and Suzanne M. Garland. Department of General Practice, Department of Obstetrics and Gynaecology, University of Melbourne, Carlton, Department of Microbiology and Infectious Diseases, Royal Women’s Hospital, Melbourne, Victoria, Australia. Journal of Clinical Microbiology, September 2006, p. 3213-3217, Vol. 44, No. 9